JP2017108405A - Method and apparatus for measuring filtering characteristic, pre-equalizer and communication equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method and apparatus for measuring a filtering characteristic, pre-equalizer and communication equipment.SOLUTION: An apparatus for measuring a filtering characteristic includes: a first measuring unit configured to measure multiple pieces of first average power of multiple first signals obtained after multiple first transmission signals pass through a transmitting end filtering module and are modulated, frequencies of the multiple first transmission signals being different; and a first processing unit configured to determine a filtering characteristic of the transmitting end according to the first average power, amplitudes of the first transmission signals and a first predefined correspondence relationship between average power of signals after passing through the transmitting end filtering module and being modulated and a product of amplitudes of the signals and the filtering characteristic of the transmitting end.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a communication technical field, and more particularly, to a filtering characteristic measurement method and apparatus, a play equalizer, and a communication apparatus.

  With the demand for cost reduction, miniaturization, and flexible arrangement of optical communication systems, the optical and electrical bandwidths of transmitters in optical communication systems are decreasing due to various causes. Currently, the narrow bandwidth problem can be overcome using pre-equalization, pre-distortion, and pre-emphasis techniques in the digital domain.

  FIG. 1 is a diagram illustrating a transceiver that employs digital play equalization technology in the prior art. As shown in FIG. 1, the transceiver 100 includes a transmitter 101, a pre-equalizer 102, a DAC module 103, a laser 105, an optical modulator 104, an optical coherent demodulator 106, a local laser 107, an ADC module 108, and a receiver 109. including. The optical modulator 105 may further include an interface that can be inserted / removed, an electric drive amplifier, and the like. Among them, the transmitter 101 transmits a digital electric signal. Filtering damage (damage due to filtering) of each subsequent filtering module at the transmitting end, for example, the digital-to-analog conversion module 103 or the optical modulator 104, to the transmitted digital electrical signal is caused by the pre-equalizer 102. Pre-compensation. The compensated digital electric signal is converted into an analog electric signal via the digital-analog conversion module 103, and then modulated by the optical modulator 104 and output as an optical signal. The optical signal is demodulated into an analog electrical signal through an optical coherent demodulator 106 and converted into a digital electrical signal by an ADC module 108. Thereafter, the receiver 109 receives the digital electrical signal described above. Here, filtering damage caused by each transmission end filtering module subsequent to the pre-equalizer 102 in the transceiver, that is, the DAC module 103 and the optical modulator 104 is referred to as transmission end filtering characteristics.

  Currently, pre-coalization processing can be performed using common frequency domain or time domain methods. The coefficients of the pre-equalizer can be obtained by employing a plurality of conventional techniques, for example, zero forcing, minimum mean square error, and the like. However, all of these methods need to grasp the transmission end filtering characteristics.

  At present, a measuring instrument is usually employed to measure the transmitting end or receiving end filtering characteristics, so that the measurement cost is high and large-scale use is difficult.

  Embodiments of the present invention provide a filtering characteristic measurement method and apparatus, a play equalizer, and a communication apparatus. The method can determine the transmission end filtering characteristics using the transmitter or the transceiver itself, i.e., the signal after passing through the filtering module and the characteristics of the optical modulator, so that an additional instrument can be used. It is not necessary to use and measure, thereby avoiding the problem of high cost and large-scale unusable due to instrumental measurement of filtering characteristics.

  The above-described object of the embodiment of the present invention can be realized by the following technical solution.

According to a first aspect of an embodiment of the present invention, a filtering characteristic measuring device is provided, of which the device is
Measuring a plurality of first average powers of a plurality of first signals obtained after the plurality of first transmission signals are modulated through a transmission end filtering module, A first measuring unit having different frequencies; and the first average power, the amplitude of the first transmission signal, and the average power (P) after the signal is modulated through the transmitting end filtering module, and the amplitude of the signal (A) and a first processing unit for determining the transmission end filtering characteristic based on a first predetermined correspondence relationship between a product (A × G (f)) of the transmission end filtering characteristic G (f) Including.

According to a second aspect of an embodiment of the present invention, a play equalizer is provided, the play equalizer comprising:
Measuring a plurality of first average powers of a plurality of first signals obtained after the plurality of first transmission signals are modulated through a transmission end filtering module, The frequency is different, and the first average power, the amplitude of the first transmission signal, and the average power (P) after the signal is modulated through the transmission end filtering module, and the amplitude (A) of the signal, A characteristic measuring unit for determining the transmission end filtering characteristic based on a first predetermined correspondence with a product (A × G (f)) with the transmission end filtering characteristic G (f); and the transmission end filtering characteristic And a pre-equalization unit for performing a pre-coalization process on the transmission signal using the pre-equalizer coefficient.

  According to a third aspect of the embodiment of the present invention, a communication device is provided, and the communication device includes the filtering characteristic measurement device according to the first aspect described above.

  A beneficial effect of embodiments of the present invention is that the transmitter or transceiver itself can be used to determine the transmit end filtering characteristics using the signal after passing through the filtering module and the characteristics of the optical modulator. This eliminates the need to measure with additional instruments, thereby avoiding the high cost and unusable problems associated with instrumentation of filtering characteristics.

It is a block diagram of the transmitter / receiver which employ | adopts the play domainization technique of the digital domain in a prior art. 3 is a flowchart of a filtering characteristic measurement method in Embodiment 1. 3 is a flowchart of an implementation method of a first predetermined correspondence determining method according to Embodiment 1. FIG. 6 is a configuration diagram of a filtering characteristic measuring apparatus in Embodiment 2. 6 is a configuration diagram of a first confirmation unit in Embodiment 2. FIG. 6 is a configuration diagram of a communication system in Embodiment 3. FIG. FIG. 6 is a configuration diagram of a communication device in Embodiment 4. FIG. 10 is a diagram illustrating an implementation method of a filtering characteristic measurement device according to a fifth embodiment. FIG. 10 is a diagram illustrating an implementation method of a filtering characteristic measurement device according to a sixth embodiment. FIG. 10 is a configuration diagram of a play equalizer according to a seventh embodiment.

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the accompanying drawings.

  In the embodiment, the transmission end filtering characteristic refers to filtering damage by the transmitter filtering module or the transmission end filtering module of the transceiver, and is represented by G (f).

  In the prior art, a measuring instrument is usually employed to measure the transmission end or reception end filtering characteristics, so that the measurement cost is high and large-scale use is difficult. In the process of realizing the present invention, the inventor discovered the following. That is, when the pre-equalizer at the transmission end of the transmitter or the transmitter / receiver does not operate, the transmission end transmits a transmission signal having an amplitude of A and a center frequency of f. After passing, the signal becomes a modulation waiting signal, the amplitude of the signal is A × G (f), and the average power P of the signal after being modulated based on the characteristics of the optical modulator is A × G In other words, there is a correspondence between P and A × G (f). In this way, a plurality of transmission signals having different frequencies are transmitted, and the average power P of the signal after each transmission signal is modulated through the filtering module is measured, and then transmission end filtering is performed based on the correspondence relationship. The characteristic G (f) can be obtained. Therefore, the filtering characteristic measurement method of the embodiment of the present invention determines the transmission end filtering characteristic using the transmitter or the transceiver itself, that is, using the signal after passing through the filtering module and the characteristic of the optical modulator. This eliminates the need to measure with additional instruments, thereby avoiding the high cost and large scale unusable problems associated with instrumentation of filtering characteristics.

  FIG. 2 is a flowchart of the filtering characteristic measuring method according to the first embodiment of the present invention. As shown in FIG. 2, the method includes the following steps.

Step 201: transmitting a plurality of first transmission signals of different frequencies;
Step 202: obtaining a plurality of modulated first signals after each of the plurality of first transmission signals is modulated through a transmission end filtering module;
Step 203: measuring a plurality of first average powers of the plurality of first signals;
Step 204: The first average power, the amplitude of the first transmission signal, the average power (P) after the signal is modulated through the transmission end filtering module, the amplitude (A) of the signal and transmission end filtering Based on the first predetermined correspondence relationship with the product (A × G (f)) with the characteristic G (f), the transmission end filtering characteristic is determined.

  As can be seen from this embodiment, the transmission end filtering characteristics are obtained by using the characteristics of a plurality of signals and modulators after passing through the filtering module of the transmitter or the transceiver, that is, using the transmitter or the transceiver itself. Since it can be determined, there is no need to measure with an additional instrument, thereby avoiding the high cost and unusable problems of instrumentation of filtering characteristics.

  In the present embodiment, the first transmission signal in step 201 is represented by S (f), which may be a narrowband signal. The narrowband signal refers to a signal whose signal bandwidth is relatively small compared to the system bandwidth, and the level of the signal bandwidth is relatively small (level) is related to the frequency resolution indicating the filtering characteristics. Of which, the filtering characteristics are considered uniform within the frequency resolution, and the signal can be considered a narrowband signal when the bandwidth of the signal is less than the frequency resolution.

  In this embodiment, the narrowband signal may be a direct current signal, a single frequency signal, a low baud rate pseudo random signal, or the like. For example, the single frequency signal may be a single frequency real signal or a single frequency pure imaginary signal. The low baud rate pseudo-random signal may be a random real signal, a random pure imaginary signal, a random complex signal, or the like, but the present embodiment is not limited to this.

  In the present embodiment, the amplitudes of the plurality of first transmission signals may be the same or different. Among them, when the amplitudes of the plurality of first transmission signals are different in order to improve the accuracy of the measurement of the first average power, the amplitude of the first transmission signal is increased as the frequency of the first transmission signal is increased. It is set to increase, in other words, it is set to increase as G (f) decreases. This is because when the frequency of the first transmission signal is relatively large, if G (f) is relatively small, A × G (f) is relatively small, that is, the average power P is also relatively small, so that the measurement error is small. This is because it is relatively large. Therefore, when the frequency is relatively large, the amplitude of the first transmission signal is also set to be large, thereby increasing the average power and reducing the measurement error.

  In the present embodiment, in step 201, the transmitter or transmitter / receiver transmitter may be employed to transmit the first transmission signal, and in step 202, the transmission end filtering module is configured to send a measurement waiting transmission end filtering characteristic. This is a transmission end filtering module of the transmitter or the transmitter / receiver. The transceiver 100 shown in FIG. 1 is taken as an example. When measuring the transmission end filtering characteristics, first, the pre-equalizer 102 of the transceiver 100 is disabled, and the transmitter 101 is configured to transmit a plurality of first transmission signals having different frequencies (that is, first measurement signals). The amplitude of the first transmission signal may be the same or different. After the plurality of first transmission signals are modulated by passing through the transmission end filtering module, for example, after passing through the DAC module 103 and the optical modulator 104, a plurality of modulated first signals can be obtained. . Note that the transceiver 100 shown in FIG. 1 is only a specific example, and the present embodiment is not limited to such a structure. Further, the transceiver and the filtering module may include other components according to needs, but an exhaustive description is omitted here.

  In this embodiment, when transmitting the above first transmission signal in step 201, the transmitter or the existing transmitter of the transmitter / receiver is reused, but instead, one new transmitter is used as the dedicated transmitter. You may install in order to transmit a transmission signal. Thereafter, the first measurement signal is passed through the transmission end filtering module without passing through the pre-equalizer.

  In this embodiment, in step 203, a plurality of first average powers of the plurality of first signals obtained in step 202 can be sequentially measured using a photoelectric detector, and in step 204, the first predetermined correspondence is measured. Based on the relationship, a plurality of transmitting end filtering characteristics corresponding to different frequency points can be obtained, and a final transmitting end filtering characteristic can be determined based on the plurality of transmitting end filtering characteristics.

For example, assuming that the transmission end filtering characteristics are determined using n frequency points, step 201 transmits first transmission signals of n different frequencies, for example, the signals are respectively S ₁₁ (f ), S ₁₂ (f),..., S _1n (f), and the amplitudes of the n signals are A ₁₁ , A ₁₂ ,..., A _1n , respectively. It may be the same or different. In step 202, after the n signals are respectively modulated through the filtering module, n modulated first signals can be obtained, for example, the modulated first signals are respectively S ′ ₁₁ (f), S ′ ₁₂ (f),..., S ′ _1n (f). In step 203, the average power of the n modulated first signals is measured. For example, the average power is expressed as P ₁₁ , P ₁₂ ,..., P _1n , respectively. In step 204, based on the obtained n average powers, the amplitude of the signal, and the first predetermined correspondence (represented as R (P, A × G (f))), n pieces are obtained. The transmission end filtering characteristics corresponding to different frequency points can be obtained. For example, the transmission end filtering characteristics are expressed as G ₁₁ (f), G ₁₂ (f),..., G _1n (f), respectively. The Accordingly, the final transmission end filtering characteristic G (f) can be determined based on the filtering characteristic corresponding to the n different frequency points described above.

  In the present embodiment, the transmission end filtering characteristics can be measured using the transmitter or the transceiver itself, so that the measurement is simple and low cost. In addition, a measuring apparatus that does not use a transmitter or a transmitter / receiver and includes a transmitter and a filtering module (same as a transmitter or a filtering module of a transmitter / receiver having a transmission waiting filtering characteristic), but does not include a pre-equalizer. May be used. In this case, the first transmission signal may be transmitted by the transmitter of the measuring device and then passed through the filtering module of the measuring device.

  In this embodiment, as an option, the method may further include a step (not shown) of determining the first predetermined correspondence R (P, A × G (f).

  In one implementation, the first predetermined correspondence R (P, A × G (f)) can be determined by measurement.

  FIG. 3 is a flowchart of an example of the first predetermined correspondence determining method in the present embodiment. As shown in FIG. 3, the method includes the following steps.

Step 301: Transmit a plurality of second transmission signals (second measurement signals) having the same frequency and different amplitudes;
Step 302: Acquire a plurality of second signals after modulation after the plurality of second transmission signals are respectively modulated through the transmission end filtering module;
Step 303: measuring a plurality of second average powers of the plurality of second signals;
Step 304: Determine the first predetermined correspondence relationship based on the amplitudes of the plurality of second transmission signals and the plurality of second average powers.

  In the present embodiment, steps 301 and 302 are the same as steps 201 and 202, and thus detailed description thereof is omitted here.

In the present embodiment, the second transmission signal S ₂ (f) may be a narrowband signal, and its specific type is the same as that of the first transmission signal, and therefore detailed description thereof is omitted here. To do.

For example, in step 301, n second transmission signals having the same frequency f ₀ and different amplitudes are transmitted. For example, the second transmission signals are S ₂₁ (f ₀ ), S ₂₂ (f ₀ ), .., S _2n (f ₀ ), and the amplitudes of the n second transmission signals are respectively represented as A ₂₁ , A ₂₂ ,..., A _2n .

In step 302, after the n second transmission signals are respectively modulated through the filtering module, n modulated second signals are obtained, for example, the modulated second signals are respectively S _{'21 (f 0), S} ' 22 (f 0), ..., denoted as S _'2n (f _0). In this embodiment, when the second transmission signal is a narrowband signal, G (f ₀ ) can be regarded as 1, so the second signal is
S ' _2i (f ₀ ) = S _2i (f ₀ ) × G (f ₀ ) = S _2i (f ₀ )
And i is 1 to n.

In step 303, the photoelectric detector can be used to measure a plurality of second average powers of the plurality of second signals, the second average powers being P ₂₁ , P ₂₂ ,..., P _2n , respectively. It is expressed.

In step 304, based on the plurality of second average power and the amplitude of the corresponding second transmission signal, a correspondence relationship between the plurality of second average power and the plurality of amplitudes is determined, of which the average power of the modulated signal is determined. Since P is determined by A × G (f) and G (f ₀ ) is regarded as 1, the correspondence between the plurality of average powers and the plurality of amplitudes is the first predetermined correspondence R (P, A × G (f)).

  In other implementations, the first predetermined correspondence R (P, A × G (f)) can be determined based on parameters of the transmitter or the transceiver.

であり、そのうち、V_piは、前記MZM変調器の位相変化πに必要な電圧を表し、Pは、変調後の信号の平均パワーを表し、G(f)は、前記送信端フィルタリング特性を表し、Aは、信号の振幅を表し、J₀()は、Bessel関数を表す。ここで、変調器がMZM変調器であるので、例えば、送信信号が
Asin(2πft)G(f)
であり、且つ変調後のローパス信号が
sin(Aπsin(2πft)G(f)/2V_pi)
と表される場合、光瞬時パワーは、

であり、即ち、

である。 For example, when the modulator is an MZM (Mach-Zehnder Modulator) modulator, the first predetermined correspondence relationship is

And a, of which, V _pi represents the voltage required for phase changes π of said MZM modulator, P is represents the average power of the modulated signal, G (f) represents the transmitting stage filtering characteristic , A represents the amplitude of the signal, and J ₀ () represents the Bessel function. Here, since the modulator is an MZM modulator, for example, the transmission signal is
Asin (2πft) G (f)
And the low-pass signal after modulation is
sin (Aπsin (2πft) G (f) / 2V _pi )
The instantaneous optical power is

That is,

It is.

  In this embodiment, as an option, when using a transmitter or a transmitter / transmitter filtering module at the steps 201 and 202, the method further comprises: It may include setting so that the play equalizer does not operate.

  As can be seen from the present embodiment, using the transmitter or the transceiver itself, that is, using the average power of the modulated first signal, the amplitude of the first transmission signal, and the characteristics of the optical modulator, Since the filtering characteristics can be determined, there is no need to measure with additional instruments, thereby avoiding the high cost and large scale unusable problems due to instrumentation of filtering characteristics.

  The second embodiment of the present invention further provides a filtering characteristic measuring apparatus. Since the principle by which the apparatus solves the problem is the same as that of the method of the first embodiment, the specific implementation can refer to the implementation of the method of the first embodiment, and the duplicate description is omitted here. To do.

  FIG. 4 is a configuration diagram of an implementation system of the apparatus according to the second embodiment. As shown in FIG. 4, the apparatus 400 includes the following.

First measurement unit 401: measuring a plurality of first average powers of a plurality of first signals obtained after a plurality of first transmission signals are modulated through a transmission end filtering module, and The frequency is different;
First processing unit 402: the first average power, the amplitude of the first transmission signal, the average power (P) after the signal is modulated through the transmission end filtering module, the amplitude and transmission of the signal Based on the first predetermined correspondence relationship with the product (A × G (f)) with the end filtering characteristic, the transmitting end filtering characteristic is determined.

  In the present embodiment, the specific implementation method of the first measurement unit 401 and the first processing unit 402 can refer to steps 203 to 204 in the first embodiment, and thus detailed description thereof is omitted here.

  In this embodiment, as an option, the apparatus 400 may further include a first determination unit 403, which is used to determine the first predetermined correspondence.

  In one implementation, the first confirmation unit 403 can obtain the first predetermined correspondence in a measurement manner. In this case, the configuration of the first confirmation unit 403 is as follows.

  FIG. 5 is a configuration diagram of an implementation method of the first determination unit 403. As shown in FIG. 5, the first confirmation unit 403 includes the following.

Second measurement unit 501: measuring a plurality of second average powers of a plurality of second signals obtained after the plurality of second transmission signals are modulated through the transmission end filtering module, , The frequency is the same, the amplitude is different;
Second determination unit 502: The first predetermined correspondence is determined based on the amplitudes of the plurality of second transmission signals and the plurality of second average powers.

  In the present embodiment, the specific implementation method of the second measurement unit 501 and the second determination unit 502 can refer to steps 303 to 304 in the first embodiment, and the duplicate description thereof is omitted here.

と確定し、そのうち、V_piは、MZM変調器の位相変化πに必要な電圧を表し、Pは、変調後の信号の平均パワーを表し、G(f)は、送信端フィルタリング特性を表し、Aは、信号の振幅を表し、J₀()は、Bessel関数を表す。 In other embodiments, the first determination unit 403 can determine the first predetermined correspondence based on transmitter or transceiver parameters. In this case, when the modulator is an MZM modulator, the first determination unit 403 satisfies the first predetermined correspondence relationship.

Where V _pi represents the voltage required for the phase change π of the MZM modulator, P represents the average power of the modulated signal, G (f) represents the transmit end filtering characteristic, A represents the amplitude of the signal, and J ₀ () represents the Bessel function.

  In the present embodiment, the amplitudes of the plurality of first transmission signals may be the same or different. Among them, when the amplitudes of the plurality of first transmission signals are different, the amplitude of the first transmission signal increases as the frequency of the first transmission signal increases, and the effect is the same as in the first embodiment. Here, detailed description thereof is omitted.

  In the present embodiment, the first transmission signal and the second transmission signal may be narrowband signals, and are the same as in the first embodiment, so the contents are merged here, and here, the detailed description thereof Is omitted.

  In this embodiment, as an option, when using a transmitter or transceiver transmitter sum filtering module, the apparatus 400 may further include a setting unit (not shown), which is the transmitter or transceiver of the transmitter or transceiver. Although used to set the play equalizer so that the play equalizer does not operate, the present invention is not limited to this, and the setting unit may be provided in a transmitter, a receiver, or a transceiver.

  In this embodiment, a communication device having a measurement waiting transmission end filtering characteristic, for example, a transmitter or a transmitter of a transmitter / receiver transmits the first transmission signal, and the communication device has a transmission end filtering of a measurement waiting transmission end filtering characteristic. After passing the module, the device 400 can then determine the transmit end filtering characteristics based on the obtained first signal.

  In the present embodiment, the first measurement unit 401 can be realized by a photoelectric detector PD.

  As can be seen from the present embodiment, the transmission end filtering characteristics can be determined using the transmitter or the transceiver itself, that is, using the amplitude of the transmission signal, the signal power after modulation, and the characteristics of the optical modulator. This eliminates the need to measure with additional instruments, thereby avoiding the high cost and unusable problems associated with instrumentation of filtering characteristics.

  Embodiments of the present invention further provide a communication system, which includes the filtering characteristic measurement apparatus 400 described in Embodiment 2, and further includes a communication apparatus, which is a transmitter or a transceiver. It may be.

  FIG. 6 is a configuration diagram of a communication system in Embodiment 3 of the present invention. As shown in FIG. 3, the communication system 600 includes the filtering characteristic measuring apparatus 400 described in the second embodiment for measuring the transmission end filtering characteristics, and the configuration thereof is the same as that of the above-described embodiment. Here, detailed description thereof is omitted.

  When the communication device 602 is a transmitter / receiver, FIG. 1 can be referred to for a specific configuration diagram thereof, and therefore, redundant description thereof is omitted here. The difference from the transceiver in FIG. 1 is that, in this embodiment, the transmitter in the transceiver is used to transmit the first transmission signal and / or the second transmission signal. Since the specific implementation method of the second transmission signal can refer to the first embodiment, detailed description thereof is omitted here.

  When the communication device 602 is a transmitter, it may include a transmitter 101, a pre-equalizer 102, a DAC module 103, an optical modulator 104, and a laser 105 as shown in FIG. The difference between the transmitter 101, the pre-equalizer 102, the DAC module 103, the optical modulator 104, and the laser 105 is that, in this embodiment, the transmitter in the transmitter transmits the first transmission signal and / or the second transmission signal. Since a specific implementation method of the first transmission signal and the second transmission signal can be referred to the first embodiment, detailed description thereof is omitted here.

  In this embodiment, when measuring the transmission end filtering characteristics, first, the setting unit (which may be installed in the transmitter or the transceiver) in the filtering characteristic measuring apparatus 400 in the communication system 600 is used. After the pre-equalizer is disabled, the first transmission signal is transmitted by the transmitter of the communication device 602, and after passing through the transmission end filtering module, the first signal is acquired, and then The first signal is transmitted to the filtering characteristic measuring apparatus 400. Thereafter, the apparatus 400 can determine the final transmission end filtering characteristics, and the specific method thereof is the same as that of the first embodiment, and thus detailed description thereof is omitted here.

  As can be seen from the present embodiment, the transmission end filtering characteristics can be determined using the transmitter or the transceiver itself, that is, using the amplitude of the transmission signal, the signal power after modulation, and the characteristics of the optical modulator. This eliminates the need to measure with additional instruments, thereby avoiding the high cost and unusable problems associated with instrumentation of filtering characteristics.

  Embodiment 4 of the present invention provides a communication device, which is different from the communication device in Embodiment 3 in that, in this embodiment, the function of the filtering characteristic measuring device described in Embodiment 2 is added to the communication device. To be integrated. The communication device may be a transmitter or a transceiver.

  FIG. 7 is a configuration diagram of a communication apparatus according to the present embodiment. As shown in FIG. 7, the communication device 700 includes a central processing unit (CPU) 701 and a storage unit 702, and the storage unit 702 is coupled to the central processing unit 701. In addition, this figure is only an illustration, A telecommunication function or another function can also be implement | achieved by performing supplement or substitution to this structure using another type of structure.

  In one implementation method, the function of the filtering characteristic measurement device 400 described in the second embodiment can be integrated into the central processing unit 701.

  Among them, the central processing unit 701 may be configured as follows, that is, a plurality of first signals of a plurality of first signals obtained after a plurality of first transmission signals are modulated through a transmission end filtering module. The average power is measured, and the frequencies of the plurality of first transmission signals are different; the first average power, the amplitude of the first transmission signal, and the average power after the signal is modulated through the transmission end filtering module ( P) and the transmission end filtering characteristics are determined based on a first predetermined correspondence between the signal amplitude (A) and the product (A × G (f)) of the transmission end filtering characteristics G (f). .

  Of these, the central processing unit 701 may be further configured to determine the first predetermined correspondence.

  In one implementation, the central processing unit 701 may be configured as follows: a plurality of second signals obtained after the plurality of second transmission signals have passed through the transmitting end filtering module. Two average powers are obtained, the frequencies of the plurality of second transmission signals are the same and the amplitudes are different; based on the amplitudes of the plurality of second transmission signals and the plurality of second average powers, the first predetermined power Determine the correspondence.

と確定し、そのうち、V_piは、MZM変調器の位相変化πに必要な電圧を表し、Pは、変調後の信号の平均パワーを表し、G(f)は、送信端フィルタリング特性を表し、Aは、信号の振幅を表し、J₀()は、Bessel関数を表す。 In another implementation, the central processing unit 701 may be configured as follows, that is, when the modulator is an MZM modulator, the first predetermined correspondence relationship is

Where V _pi represents the voltage required for the phase change π of the MZM modulator, P represents the average power of the modulated signal, G (f) represents the transmit end filtering characteristic, A represents the amplitude of the signal, and J ₀ () represents the Bessel function.

  Among them, the plurality of first transmission signals have the same amplitude or different amplitudes.

  Among them, when the amplitudes of the plurality of first transmission signals are different, the amplitude of the first transmission signal increases as the frequency of the first transmission signal increases.

  Among them, the first transmission signal or the second transmission signal is a narrowband signal. In another implementation method, the filtering characteristic measurement device 400 described in the second embodiment may be configured independently of the central processing unit 701. For example, the device 400 is configured as a chip connected to the central processing unit 701. (Refer to 703 in FIG. 7), and the function of the device 703 can be realized by the control of the central processing unit 701.

  As shown in FIG. 7, the communication device 700 may further include a communication module 704, an input unit 705, a display 707, and a power source 708. Note that the communication device 700 does not necessarily include all the components illustrated in FIG. Further, the communication device 700 may further include parts not shown in FIG. 7, and the prior art can be referred to for this.

  In the present embodiment, the communication device 700 may be a transmitter. In this case, the apparatus 700 further includes a laser 706, and the communication module 704 is a signal transmission module, and the configuration thereof may be the same as that of a conventional transmitter, for example, as shown in FIG. The transmitter 101, the pre-equalizer 102, the DAC module 103, and the optical modulator 104 may be included. Note that the configuration of the communication module 704 is not limited to this.

  In the present embodiment, the communication device 700 may be a transceiver. In this case, the apparatus 700 may further include a laser 707 and a local laser (not shown), and the communication module 704 is a signal transmission and reception module, the configuration of which is the same as a conventional transceiver. It's okay. For example, the transmission module may be the same as the transmitter. Further, as shown in FIG. 1, the receiving module may include an optical coherent demodulator 107, an ADC module 108, and a receiver 109. Note that the configuration of the communication module 704 is not limited to this.

  Among them, the central processing unit 701 may be further configured as follows, that is, the transmitter in the communication module 704 described above transmits the first transmission signal and / or the second transmission signal, and the After the first transmission signal and / or the second transmission signal is modulated through the transmission end filtering module, control is performed so as to obtain a modulated first signal.

  In the present embodiment, the communication device may further include a photoelectric detector (not shown), and the central processing unit 701 is configured such that the power of the first signal and / or the second signal after the photoelectric detector is modulated. And the transmission end filtering characteristic can be controlled using the measurement result.

  As shown in FIG. 7, the central processing unit 701 may be referred to as a controller or operational controller and may include a microprocessor or other processor unit and / or logic unit. The central processing unit 701 can receive input and can control the operation of each component of the communication device 700.

  Among them, the storage device 702 may be, for example, one or more of a buffer, a fresh memory, an HDD, a removable medium, a volatile storage, a non-volatile storage, or other suitable device. Predefined or configured information can be stored, and an information processing program can also be stored. The central processing unit 701 can execute the program stored in the storage device 702 in order to realize information storage or processing. Since the functions of the other parts are the same as those of the prior art, detailed description thereof is omitted here. Each component of the communication device 700 can also be realized by dedicated hardware, firmware, software, or a combination thereof, all of which belong to the scope of the present invention.

  In the present embodiment, at the time of filtering characteristic measurement, first, the setting unit in the filtering characteristic measuring apparatus 703 is made to prevent the pre-equalizer in the communication module 704 from operating, and then the transmitter in the communication module 704 is controlled by the control of the CPU. The first transmission signal of a different frequency is transmitted, and after passing through each filtering module at the transmission end and modulated, the first signal after modulation is obtained, and then obtained by the control of the CPU. The first signal is transmitted to the filtering characteristic measuring apparatus 703. After that, the device 703 can determine the final transmission end filtering characteristics, and the specific method thereof is the same as that of the first embodiment, and thus detailed description thereof is omitted here.

  As can be seen from the present embodiment, the transmission end filtering characteristics can be measured using the communication device itself according to the present embodiment, so that it is not necessary to perform the measurement using an additional instrument. The problem of high cost and large scale unusable due to instrumental measurement of characteristics can be avoided.

  The fifth embodiment further provides a filtering characteristic measurement device, which differs from the device 400 of the second embodiment in that this embodiment does not use an existing transmitter or transmitter / receiver transmitter, Only the transmission end filtering module of an existing transmitter or transceiver is used.

  FIG. 8 is a configuration diagram of an implementation method of the apparatus according to the fifth embodiment. As shown in FIG. 8, the apparatus 800 includes a first measurement unit 801, a first processing unit 802, and a first determination unit 803, and the specific implementation method thereof is the first measurement unit 401 in the second embodiment. Since the first processing unit 402 and the first determination unit 403 can be referred to, detailed description thereof is omitted here.

  In this embodiment, the apparatus 800 may further include a first transmission unit 804, which transmits a plurality of first transmission signals having different frequencies to obtain a modulated first signal. The first transmission signal is used to directly transmit an existing transmitter or a transmission end filtering module of a transceiver. The first measurement unit 801 can acquire the first signal and measure a plurality of first average powers of the plurality of first signals, and the first processing unit 802 determines a final transmission end filtering characteristic. Since the specific method is the same as that of the first embodiment, detailed description thereof is omitted here.

  Among them, the first transmission unit 804 further transmits a plurality of second transmission signals having the same frequency but different amplitudes, so as to obtain a second signal after modulation. Used to transmit directly to the existing transmitter or transmitter end filtering module of the transceiver, after which the first determination unit 803 can determine the first predetermined correspondence, the specific method is: Since it is the same as that of Example 1, the detailed description is abbreviate | omitted here.

  In this embodiment, since it is not necessary to pass the first transmission signal transmitted by the first transmission unit 804 through the pre-equalizer of the existing transmitter or transceiver, the apparatus needs to include the setting unit in the second embodiment. Absent.

  In this embodiment, the filtering characteristic measuring apparatus 800 transmits a plurality of first transmission signals having different frequencies, and transmits a plurality of first transmission signals to a communication apparatus (transmitter or transmission end filtering module of a transceiver). The communication device receives a plurality of first transmission signals transmitted by the device 800 and modulates the plurality of first transmission signals by passing through a transmitter end filtering module of its own transmitter or transceiver; After that, the modulated first signal is transmitted to the device 800; the device 800 receives the first signal returned by the communication device, and can determine the final transmitting end filtering characteristic, Since the specific determination method is the same as that in the first embodiment, detailed description thereof is omitted here.

  As can be seen from the present embodiment, the transmission end filtering characteristics can be measured using the communication device itself according to the present embodiment, so that it is not necessary to perform the measurement using an additional instrument. The problem of high cost and large scale unusable due to instrumental measurement of characteristics can be avoided.

  The sixth embodiment further provides an apparatus for measuring filtering characteristics, which is different from the device 800 in the fifth embodiment in that the present embodiment does not use an existing transmitter or a transmission end filtering module of a transceiver. There is.

  FIG. 9 is a configuration diagram of an implementation system of the apparatus according to the sixth embodiment. As shown in FIG. 9, the apparatus 900 includes a first measurement unit 901, a first processing unit 902, a first determination unit 903, and a second transmission unit 904. The first measurement unit 801, the first processing unit 802, the first determination unit 803, and the first transmission unit 804 can be referred to, and detailed description thereof is omitted here.

  In this embodiment, the apparatus 900 may further include a transmission end filtering module 905, which is the same as the transmitter or transceiver filtering module of the transmission end filtering characteristics awaiting measurement, and the second transmission unit 904. After the plurality of first transmission signals are transmitted to the transmission end filtering module 905 and modulated, the first signal after modulation is obtained, and then the first measurement unit 901 includes the plurality of first signals. Since the first processing unit 902 can determine the final transmission end filtering characteristics and the specific method is the same as in Example 1, Detailed description thereof is omitted.

  Among them, when the first determination unit 903 determines the first predetermined correspondence, the second transmission signal transmitted by the second transmission unit 904 having the same frequency but different amplitude is transmitted from the transmission end filtering module 905. After the modulation, the second signal after modulation is obtained, and then the first determination unit 903 can determine the first predetermined correspondence relationship, and a specific method thereof is the same as in the first embodiment. Since it is the same, the detailed description is abbreviate | omitted here.

  In this embodiment, the apparatus 900 can transmit the filtering characteristic to the communication apparatus after determining the transmission end filtering characteristic, for example, can transmit it to the transceiver or transmitter pre-equalizer, Thus, the play equalizer can determine the coefficients of the play equalizer for the play equalization process based on the transmission end filtering characteristic.

  As can be seen from the present embodiment, the transmission end filtering is determined by determining the transmission end filtering characteristics based on the average power of the modulated first signal, the amplitude of the first transmission signal, and the characteristics of the optical modulator. Since the characteristics can be established, there is no need to measure with additional instruments, thereby avoiding the high cost and large scale unusable problems due to instrumentation of filtering characteristics. It is also possible to obtain a pre-equalizer coefficient based on the filtering characteristics measured by the above-described method, and to compensate for filtering damage caused by the filtering module using the pre-equalizer coefficient.

  The seventh embodiment further provides a play equalizer. FIG. 10 is a configuration diagram of the play equalizer in the present embodiment. The play equalizer 1000 includes the following.

Characteristic measuring unit 1001: including a filtering characteristic measuring device, used for determining transmission end filtering characteristics;
Pre-equalization unit 1002: Determines the coefficients of the pre-equalizer based on the transmission end filtering characteristics, and performs a pre-coalization process on the transmission signal using the coefficients of the pre-equalizer.

  Among them, the specific implementation method of the characteristic measurement unit 1001 can refer to any one of the filtering characteristic measurement apparatuses in the embodiment 2, 5 or 6, and the pre-coalization unit 1002 includes zero forcing and minimum The coefficient of the play equalizer may be determined by adopting a method such as a mean square error, or the CMA (constant modulus algorithm) may be adopted and the received signal may be pre-coalized using the coefficient. Although it is good, a present Example is not limited to this.

  The eighth embodiment further provides a communication device. The communication device may be a transceiver or a transmitter. The communication device includes the pre-equalizer 1000 in the seventh embodiment, and a specific implementation scheme thereof can refer to the seventh embodiment, and thus detailed description thereof is omitted here.

  As can be seen from the present embodiment, the transmission end filtering characteristics can be determined based on the average power of the modulated first signal, the amplitude of the first transmission signal, and the characteristics of the optical modulator. Therefore, it is possible to avoid the problem of high cost and large-scale unusable due to the measurement of the filtering characteristics. It is also possible to obtain a pre-equalizer coefficient based on the filtering characteristics measured by the method described above, and to compensate for filtering damage by the filtering module using the pre-equalizer coefficient.

  Embodiments of the present invention further provide a computer-readable program, of which, when executing the program in a filtering characteristic measuring device, the program is described in the first embodiment in the filtering characteristic measuring device on a computer. The filtering characteristic measurement method is executed.

  The embodiment of the present invention further provides a storage medium storing a computer readable program, wherein the computer readable program executes the filtering characteristic measuring method described in the first embodiment in a filtering characteristic measuring apparatus on a computer. Let

  Also, the apparatus and method according to the embodiments of the present invention may be realized by software, hardware, or a combination of hardware and software. The present invention also relates to such a computer-readable program, that is, when the program is executed by a logic component, the logic component can realize the above-described apparatus or component, or The above-described method or its steps can be realized in the logic component. The present invention further relates to a storage medium for storing the above-described program, such as a hard disk, a magnetic disk, an optical disk, a DVD, a flash memory, and the like.

  Further, regarding the above-described embodiment, additional notes are also disclosed as follows.

(Appendix 1)
A filtering characteristic measuring device comprising:
Measuring a plurality of first average powers of a plurality of first signals obtained after a plurality of first transmission signals are modulated through a transmission end filtering module, the plurality of first transmission signals A first measurement unit having different frequencies; and the first average power, the amplitude of the first transmission signal, and the average power (P) after the signal is modulated through the transmission end filtering module, and the amplitude of the signal (A) and a first processing unit for determining the transmission end filtering characteristic based on a first predetermined correspondence relationship between a product (A × G (f)) of the transmission end filtering characteristic G (f) Including the device.

(Appendix 2)
The apparatus according to appendix 1, further comprising:
An apparatus including a first determination unit for determining the first predetermined correspondence.

(Appendix 3)
The apparatus according to appendix 2, wherein
The first confirmation unit is
For measuring a plurality of second average powers of a plurality of second signals obtained after a plurality of second transmission signals are modulated through a transmission end filtering module, wherein the plurality of second transmission signals are A second measurement unit having the same frequency and different amplitudes; and a second measurement unit for determining the first predetermined correspondence relationship based on the amplitudes of the plurality of second transmission signals and the plurality of second average powers A device containing two deterministic units.

と確定するための第三確定ユニットを含み、
V_piは、MZM変調器の位相変化πに必要な電圧を表し、Pは、変調後の信号の平均パワーを表し、G(f)は、送信端フィルタリング特性を表し、Aは、信号の振幅を表し、J₀()は、Bessel関数を表す、装置。 (Appendix 4)
The apparatus according to appendix 2, wherein
The first confirmation unit is
When the modulator is an MZM modulator, the first predetermined correspondence relationship is

Including a third confirmation unit to confirm
V _pi represents the voltage required for the phase change π of the MZM modulator, P represents the average power of the modulated signal, G (f) represents the transmission end filtering characteristics, and A represents the amplitude of the signal J ₀ () represents the Bessel function.

(Appendix 5)
The apparatus according to appendix 1, wherein
The amplitude of the plurality of first transmission signals is the same or different.

(Appendix 6)
The apparatus according to appendix 5, wherein
The apparatus, wherein when a plurality of first transmission signals have different amplitudes, the amplitude of the first transmission signal increases as the frequency of the first transmission signal increases.

(Appendix 7)
The apparatus according to appendix 1 or 3,
The apparatus wherein the first transmission signal or the second transmission signal is a narrowband signal.

(Appendix 8)
The apparatus according to appendix 1 or 3, further comprising:
A first transmission unit for transmitting the first transmission signal or the second transmission signal; or the apparatus includes a second transmission unit and the transmission end filtering module, and the second transmission unit includes the first transmission unit An apparatus for transmitting one transmission signal or the second transmission signal, wherein the first transmission signal or the second transmission signal passes through the transmission end filtering module.

(Appendix 9)
A play equalizer,
Measuring a plurality of first average powers of a plurality of first signals obtained after a plurality of first transmission signals are modulated through a transmission end filtering module, the plurality of first transmission signals The frequency is different, and the first average power, the amplitude of the first transmission signal, the average power (P) after the signal is modulated through the transmission end filtering module, and the amplitude (A) of the signal A characteristic measurement unit for determining the transmission end filtering characteristic based on a first predetermined correspondence with a product (A × G (f)) with the transmission end filtering characteristic G (f); and the transmission end filtering characteristic A pre-equalization unit for determining a pre-coefficient of the play equalizer and performing a pre-coalization process on the transmission signal using the pre-coalizer coefficient. Mu, equipment.

(Appendix 10)
A communication device,
The communication device includes the filtering characteristic measurement device according to attachment 1.

(Appendix 11)
A filtering characteristic measuring method,
Transmitting a first transmission signal having a plurality of different frequencies;
Obtaining a plurality of first signals after the plurality of the first transmission signals are modulated through a transmission end filtering module;
Measuring a plurality of first average powers of the plurality of first signals; and the first average power, the amplitude of the first transmission signal, and the average power after the signal is modulated through a transmission end filtering module ( P) and the transmission end filtering characteristics are determined based on a first predetermined correspondence between the product (A × G (f)) of the signal amplitude (A) and the transmission end filtering characteristics G (f). A method comprising:

(Appendix 12)
The method according to appendix 11, further comprising:
Determining the first predetermined correspondence.

(Appendix 13)
The method according to appendix 12, wherein
The determination of the first predetermined correspondence is as follows:
Transmitting a plurality of second transmission signals having the same frequency but different amplitudes;
Obtaining a plurality of second signals after the plurality of second transmission signals are modulated through a transmission end filtering module;
Measuring a plurality of second average powers of the plurality of second signals; and determining the first predetermined correspondence relationship based on the amplitudes of the plurality of second transmission signals and the plurality of second average powers. Including.

と確定することを含み、
V_piは、MZM変調器の位相変化πに必要な電圧を表し、Pは、変調後の信号の平均パワーを表し、G(f)は、送信端フィルタリング特性を表し、Aは、信号の振幅を表し、J₀()は、Bessel関数を表す、方法。 (Appendix 14)
The method according to appendix 12, wherein
The determination of the first predetermined correspondence is as follows:
When the modulator is an MZM modulator, the first predetermined correspondence relationship is

And confirming
V _pi represents the voltage required for the phase change π of the MZM modulator, P represents the average power of the modulated signal, G (f) represents the transmission end filtering characteristics, and A represents the amplitude of the signal Where J ₀ () represents the Bessel function.

(Appendix 15)
The method according to appendix 11, wherein
The amplitude of the plurality of first transmission signals is the same or different.

(Appendix 16)
The method according to appendix 15, wherein
The method, wherein when a plurality of first transmission signals have different amplitudes, the amplitude of the first transmission signal increases as the frequency of the first transmission signal increases.

(Appendix 17)
The method according to appendix 1, wherein
The method wherein the first transmission signal or the second transmission signal is a narrowband signal.

(Appendix 18)
The method according to appendix 11, further comprising:
A method comprising: determining a pre-equalizer coefficient based on the transmission-end filtering characteristic; and performing a pre-coalization process on the transmission signal using the pre-equalizer coefficient.

  The preferred embodiment of the present invention has been described above, but the present invention is not limited to this embodiment, and all modifications to the present invention belong to the technical scope of the present invention unless departing from the spirit of the present invention.

Claims (10)

An apparatus for measuring filtering characteristics,
A first measurement unit for measuring a plurality of first average powers of a plurality of first signals obtained after a plurality of first transmission signals are modulated through a transmission end filtering module, The first measurement unit; and the first average power, the amplitude of the first transmission signal, and the average power (P) after the signal is modulated through the transmission end filtering module; Based on the first predetermined correspondence between the product (A × G (f)) of the amplitude (A) of the signal and the transmission end filtering characteristic G (f), a first for determining the transmission end filtering characteristic An apparatus including a processing unit. The apparatus of claim 1, wherein
The apparatus further comprising a first determination unit for determining the first predetermined correspondence. The apparatus according to claim 2, wherein
The first confirmation unit is
A second measurement unit for measuring a plurality of second average powers of a plurality of second signals obtained after a plurality of second transmission signals are modulated through a transmission end filtering module, A second measurement unit having the same frequency and different amplitude; and determining the first predetermined correspondence relationship based on the amplitude of the plurality of second transmission signals and the plurality of second average powers. An apparatus comprising a second confirmation unit for. The apparatus according to claim 2, wherein
The first confirmation unit is
When the modulator is an MZM modulator, the first predetermined correspondence relationship is

Including a third confirmation unit to confirm
V _pi represents the voltage required for the phase change π of the MZM modulator, P represents the average power of the modulated signal, G (f) represents the transmission end filtering characteristics, and A represents the amplitude of the signal J ₀ () represents the Bessel function. The apparatus of claim 1, wherein
The amplitude of the plurality of first transmission signals is the same or different. The apparatus according to claim 5, wherein
The apparatus, wherein when a plurality of first transmission signals have different amplitudes, the amplitude of the first transmission signal increases as the frequency of the first transmission signal increases. The apparatus according to claim 1 or 3,
The apparatus wherein the first transmission signal or the second transmission signal is a narrowband signal. The apparatus according to claim 1 or 3,
The apparatus includes a first transmission unit for transmitting the first transmission signal or the second transmission signal; or the apparatus includes a second transmission unit and the transmission end filtering module, and the second transmission unit Transmits the first transmission signal or the second transmission signal, and the first transmission signal or the second transmission signal passes through the transmission end filtering module. A play equalizer,
A characteristic measurement unit for measuring a plurality of first average powers of a plurality of first signals obtained after a plurality of first transmission signals are modulated through a transmission end filtering module, wherein the plurality of first transmissions The frequency of the signal is different, and the first average power, the amplitude of the first transmission signal, the average power (P) after the signal is modulated through the transmission end filtering module, and the amplitude of the signal (A ) And a product (A × G (f)) of the transmission end filtering characteristic G (f) and a transmission unit filtering characteristic to determine the transmission end filtering characteristic based on a first predetermined correspondence relationship; and the transmission end Based on a filtering characteristic, a coefficient of the play equalizer is determined, and a play equalization unit for performing a play equalization process on the transmission signal using the coefficient of the play equalizer. Equipment, including knit. A communication device,
The communication device includes the filtering characteristic measurement device according to claim 1.

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